Put water with a little salt in a pot and bring to a boil. Add the pasta and cook. After 2 minutes of cooking, add the broccoli florets and cook with the pasta for about 8 more minutes.
While the pasta is cooking, set aside in a skillet over medium heat, melt the butter, add the garlic and cook for about 2 minutes.
Incorporate the flour with the butter, then add the milk, the chicken broth and season with salt and pepper. Let the sauce take shape.
Strain the pasta, also the broccoli and add to the sauce. Add salt and pepper according to your taste.
Place everything on a plate and cover with the rest of the cheese and the chopped leek. If desired, it can be baked in the oven to brown a little.